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Calcium sulfoaluminate (CSA) cements can be a solution to reduce the environmental impact of concrete,thanks to the lower energy consumption and CO2 emission during their production.Their expansive, fast setting and rapid hardening properties contribute to the growing interest of engineers for concrete construction and prefabrication.However, the durability of sulfoaluminate concretes is not clearly assessed yet, especially in acidic environments, i.e.encountered in sewer networks.A dynamic leaching test is used to study the resistance of concretes made of CSA cements, and to compare their behavior to those of ordinary Portland and GGBS cements based concretes.The test consists in the exposition of the concretes to a controlled environment, with pH (set to 3 and 5 with HNO3) and temperature (20℃) regulation.Distilled water recirculation allows the concentration of leachates aside from the exposition reactor,where a poorly ionized medium is thus maintained.Major elements (Ca, Al, S, Si, Fe, Na, K) leaching is regularly quantified by ICP-AES during the test.At the end of the test, leached depth is measured and characterized using SEM-EDX and XRD.Measured leaching speeds (in mmol.dm-2.j-1/2 and μm.j-1/2) show a better acidic resistance of CSA concretes than the reference ones manufactured with conventional cements, especially at pH 3.Thus, despite the sensibility of its main hydrate (ettringite), CSA cements are interesting binders for cement-based materials exposed to acidic environments.